Turkish Prime Minister Ahmet Davutoglu has accused Russia and other supporters of Syrian President Bashar al-Assad's regime of committing "war crimes" in Syria.

Speaking on February 4 at a fund-raising conference in London for Syrian war victims, Davutoglu said the root cause of the humanitarian crisis is "the war crimes committed by the Syrian regime" and by Islamic State (IS) militants.

He said "those who are helping the Assad regime are committing the same war crimes. I am especially saying this today because Aleppo is under heavy attack by Russian airplanes."

In Moscow, Russia's Defense Ministry spokesman Igor Konashenkov responded to Davutoglu's criticism by accusing Turkey of "intensive preparations for military intrusion" into Syria.

Konashenkov said Russia has registered "an increasing number of signs of the Turkish armed forces’ hidden preparations for active operations" within Syrian territory.

A government spokesman in Ankara said later that Moscow is making claims of Turkish military preparations in order to divert attention from its "crimes."